Improvement in manufacture op cast-metal dies



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LUKE CHAPMAN, OF COLLINSVILLE, CONNECTICUT, ASSIGNOR TO `COL-` LINSCOMPANY, OF SAME PLACE.

Letters Patent No. 97,046, dated November 23, 1869.

IMPROVEMENT IN MANUFACTURE OF CAST-METAL DIES.

The Schedule referred to in these Letters Patent ad making pan of thesame To all 'whom it may concern:

In making axes and the like, the iron constituting the bodyof the axe isfirst made into what are technically termed heads, and sometimes, insimilar manutactories, blanks77 These heads are produced by heating barsof iron of the proper dimensions to a bright-red heat, cutting them intoproper lengths, and then, by means of dies and punches, working undergreat pressure, punching the eye for the helve, and making the generalshape of the head7 something like the general shape of a finished axe.These heads are afterward subject-ed to various manipulations under tripand hand-hammers, to describe which would be foreign to the purpose ofthis specication.

In making these heads, the Collins Company have for many years used themachine patented by Elisha K. Root, which patent, I think, has expired.Latterly, they have also used the machine patented by Levi Dodge, on the12th day of March, 1861, the dies in which are'bf cast-iron.

The improvement made by me is applicable to both these machines, and toother purposes, as described hereafter herein.

Itis necessary to manufacture a large number of different varieties lofaxes, and each variety of axe requires its own setof dies. The method ofmaking these cast-irondies heretofore has been to casta blank, and thento work out, by hand, tools, and the like, the face ofthe blank, to titthe surface of the sides of the axe; this, of course, with a greatexpenditure ot' timev and skill.

I hav'e invented a much simpler process of produc- Iing these cast-irondies, in the following manner:

Fasten into the press, in the place of the dies, blanks of softlead,which shall be made ou all sides, but the face, the saine as the dies,aud shall fasten into the press in the same manner as the dies. The faceof the blanks will be smooth, and the thickness of the blank will beregulated as hereinafter described. Now, introduce between these blanksan axe of the desired pattern, apply the power to the press, and thefaces of the lead blanks will be forced into perfect moulds of the snr-Afacesof the sides of the axe. The lead blanks are now taken out of thepress, the sides trimmed and squared up, and the blanks otherwise fittedfor models for casting, and from these models can be cast as many diesas are desired. I thus produce better blanks, at aeheaper rate. v

There is one point in this process which it needs judgment to determineupon, that is,l the depth or thickness ofthe lead blanks from the faceto the back before submitting to pressure. The lead blanks should bethick enough to fill the whole surface designed, and as little thickeras possible. A trifle of thickness more or less will not atect theresult, so long as there is metal enough. Upon this point no absoluteand definite rule can be given, but any person moderately skilled indie-making can easily make a suicient estimate.

This process is applicable to the production of eastmetal dies, in allcases where the press used is strong enough to sustain the somewhatheavy pressure necessary, and when the article to he manufacturedcapable ofbeiug submitted td such pressure.

Although my process is applicable to a variety of manufactures I willnow describe one method of its l application, byreferring to drawingstiled herewith,

and to letters of reference marked thereon, forming a part of thisspecification.

In the drawings- Figure l, let a and a represent the jaws of a press,working togetl'ier-nnder strong pressure,l iinpelled by the arms b andb, which are attached to proper inotive-poner.

ln Figure 2, let c represent a blank of soft lead, ot' which c is theface, and at the back is the iron pin d, which fits into either oftheholes e.

The whole blank cjust tits into either of the beds g in the jaws of thepress. There are two ot' these blanks, one for each of beds y y.

Now,` put the blanks c and c into the beds g g, and insert the axe(Figures 4 and 5) atwise between the blanks, so that both sides shall becovered except the part shown in dotted lines. Then apply themotivepower to the press, and force the jaws together, and the resultwill be that the axe will sink into the faces of the blanks, and thatsaid faces will be a perfect mould of thesides of the axe.

It will readily be inferred, that in undergoing this pressure, theblanks will be pressed somewhat out of shape 0n the sides. They are nowtaken out of the press and trued-up, when they are ready to be used aspatterns for casting real dies of hard metal, which,

in the case just described, can be used in the press just described forthe manufacture of axe-heads.

I am aware that soft gutta-percha has been employed to receiveimpressions of fern-leaves and other delicate objects, with a view tousing such impressions 'or patterns from which to Cast .plates for;printing.

copies of such ferns and other` articles; and-' .n'r also aware' thatplaster ot' Paris is in common use fortakfing impressions for thepurposes of casting; and, therefor'e,"l d0 not claim, broadly, themethod of making patterns for (lios for casting by the use of a softmitte rial; but

What I claim :is my invention, and desire to secure by Letters Patent,is-

The improved method herein describedof Ina-king patterns from which -tomould, in sand, in't-he ordinary way, metal dies to be used for swagingaxes; that is to say, obtaining the pattern by compressing two or morepieces of lead around andv upon a.' inished axe, so ns to obtain-thereofthe exact' impression of the axe.

LUKE CHAPMAN.

Witnesses:

OLIVER F. PERRY, M. L. W. THoMsoN.

